Method of applying a label to a container having a curved portion

Abstract: A method of applying a label (L) to a container (10) which includes an intermediate portion (P) of the side wall (14) thereof which has an annular curved surface wherein the vertical height of the portion having a curved surface is a minor portion of the entire height of the container. A narrow rectangular label (L) of shrinkable material is first provided with one or more longitudinally extending strips of adhesive (15) extending intermediate the longitudinal edges of the label at the area of the label which is to contact the portion of greatest diameter on the curved portion of the container. The strip of adhesive material is shorter than the length of the label so that the adhesive material does not contact the overlapping edges of the label. An adhesive (16) is applied to the trailing edge of the label only and the label is wrapped about the compound curved portion with the adhesive strip engaging the curved portion of the container at the area of greatest diameter. The edges of the label are overlapped and bonded and the overlapped label is then shrunk into position by moving the container and label through an oven. The curved portion of the container may have a compound curvature.

Description: This invention relates to applying labels to containers by a wrap and shrink process. Background and Summary of the Invention In the application of labels to containers having curved surfaces, such as carbonated beverage containers of glass or plastic, it has been common to wrap a label of shrinkable material about the generally cylindrical side wall of a container and then shrink the label about the container. It has also been common to have the label be wrapped about a curved shoulder or heal surface of the container as well as the cylindrical side wall and then be shrunk thereon. Methods and apparatus have been used wherein adhesives or solvents are applied to the leading edge and trailing edge of the label as shown, for example, in United States patents 4,574,020, 4,632,721, 4,671,836, 4,724,029, 4,729,811 and 4,844,760. However, where the portion of the container to which the label is to be applied is curved and has a narrow vertical height relative to the height of the side wall, it has been found that it is difficult to wrap the narrow label about the curved portion of the container in an apparatus that handles many containers per minute. The leading and trailing edges tend to overlap in a skewed relationship. The problem is even more acute where the curved portion of the container has a compound curvature and the portion of the container with the greatest diameter is not centrally located with respect to the upper edge and lower edge of label. Accordingly, among the objectives of the present invention are to provide a method of applying a narrow shrinkable label by wrapping the label about a curved portion of a container and holding the label for sufficient time to permit shrinking the narrow label into conformity with the curved portion; wherein the container may have a compound curved portion and which method provides a uniform shrinkage about the compound curved portion with the upper and lower edges of the narrow label being in conformity thereto. In accordance with the invention a method is provided for applying a label to a container which includes an intermediate curved portion of the side wall thereof, which may have a compound curvature, wherein the vertical height of the curved portion is a minor portion of the entire height of the container wherein. A narrow rectangular label of shrinkable material is first provided with a continuous or interrupted longitudinally extending strip of adhesive extending intermediate the longitudinal edges of the label at the area of the label which is to contact the portion of greatest diameter on the curved portion of the container. The strip of adhesive material is shorter than the length of the label so that the adhesive material does not contact the overlapping edges of the label. The label is wrapped about the compound curved portion with the adhesive strip engaging the curved portion of the container at the area of greatest diameter. The edges are overlapped and bonded and the overlapped label is then shrunk into position by moving the container and label through an oven. The bonding of the edges may be by adhesive, solvent or heat sealing. If adhesive or solvent is used as a bonding agent, it is applied to the only trailing edge of the label. Description of the Drawings FIG. 1 is an elevational view of a container embodying the invention. FIG. 2 is a plan view of a label taken from the side which is positioned adjacent the container. FIG. 3 is a fragmentary vertical sectional view of a portion of the container in FIG. 1. FIG. 4 is a fragmentary sectional view on an enlarged scale of a portion of the wall of the container. FIG. 5 is a fragmentary elevational view of a portion of the container after the label has been wrapped about the container and before it has been shrunk on the container. FIG. 6 is a perspective view of the container with the label partially wrapped about the container. Description As shown in Fig. 1, the container 10 is made of glass or plastic and includes a base 11, a shoulder 12, a neck or finish 13 and a side wall 14. The neck 13 is threaded for receiving a closure, as where the container is used to hold carbonated beverages or liquids. A narrow rectangular label L is shrunk about a curved portion P of the container which forms an annular recess intermediate the shoulder 12 and the lower side wall 14. As shown, the vertical height of the recessed curved portion P is a minor portion of the height of the side wall 14 of the container 10. The curved portion P is shown as having a compound curvature R1, R2 wherein radius R₁ is larger and has a different center than the other radius R₂. The crest line C at the place of greatest diameter of portion P divides the curved portion P into a larger upper portion of radius R₁ and a smaller lower portion of radius R₂. As shown in Fig. 2, the label L is generally rectangular with a leading edge 17, a trailing edge 16 and side edges S and has a width substantially equal to the vertical height of the curved portion P. A hot adhesive in a narrow longitudinally extending strip 15 is applied at the inner surface of the label in a line which will face the crest line C. Preferably the strip is interrupted with portion 15a spaced from the leading edge and a portion 15b aligned with portion 15a and spaced from the trailing edge a greater distance than the portion 15a is spaced from the leading edge. As the label L is first wrapped around the container 10, the adhesive line 15 is aligned with and engages the portion of greatest diameter of the compound curvature. The leading and trailing edges are then overlapped and bonded to one another as by using adhesive, solvent or heat sealing. As shown in FIG. 2, an additional line 16 of adhesive or solvent is applied only at the trailing edge of the label L. As shown in FIG. 5, adhesive strip 15 is applied and the edges are overlapped and, bonded to hold the label L in position at least long enough for the container and the label L to be wrapped around the container, the leading and trailing edges are overlapped and the container, with the label L applied thereto, is moved through an oven to shrink the label into conformity with the compound curved portion P of the container so that the side edges S are at the axial extremities of the recessed compound curved portion P. The strip of adhesive is preferably applied by a spray gun spaced from the label so that as the label moves past the spray gun, a line of adhesive is applied. As used herein, the term adhesive is intended to cover any bonding agent that will hold the label in position as it is wrapped until the leading and trailing edges are overlapped and the container, with the label applied thereto, is moved through an oven to shrink the label into conformity with the compound curved portion P of the container such that the side edges of the label are at the axial extremities of the compound curved portion P. The label L may be made of any shrinkable material such as plastic including multilayer labels comprising a foam layer and a non-foam layer such as shown, for example, in United States patent 4,626,455. A satisfactory apparatus which can be used with the addition of a spray mechanism and the elimination of application of any bonding agent to the leading edge such as shown in United States patent 4,729,811. It can thus be seen that there has been provided a method of applying a narrow label by wrapping the label about a curved portion of the container and holding the label for sufficient time to permit shrinking the narrow label into conformity with the curved portion; wherein the container may have a compound curved portion; and which method provides a uniform shrinkage about the compound curved portion with the upper and lower edges of the narrow label being in conformity thereto.

Claims: A method of applying a label (L) to a container (10) which includes a curved portion (P) intermediate the side wall (14) thereof which has a curvature so as to form a place (C) of greatest diameter on the curved portion (P) and wherein the height of the curved portion (P) has a height which is a portion of the entire height of the container comprising providing a rectangular label (L) of shrinkable material having a leading edge (17), a trailing edge (16) and longitudinal edges, applying a strip (15) of bonding material along a longitudinally extending line extending intermediate the longitudinal edges (S) of the label (L) at the area of the label which is to contact the place (C) of greatest diameter on the curved portion (P) of the container, said strip (15) of bonding material being spaced from the leading and trailing edges (16, 17) of the label, wrapping the label (L) about the curved portion (P) with the bonding material engaging the container (10) at the place (C) of greatest diameter, overlapping the leading and trailing edges (16, 17) of the label (L), bonding the overlapped leading and trailing edges (16, 17), and shrinking the overlapped label (L) into position on the curved portion (P) of the container (10) by moving the container and label through an oven. The method set forth in claim 1 wherein said strip (15) of bonding material is interrupted. The method set forth in claim 1 or 2 wherein said curved portion (P) of said container (10) has a compound curvature (R₁, R₂) such that the crest line (C) of the curved portion (P) divides the curved portion (P) into portions of different size. The method set forth in any of claims 1 to 3 wherein said strip (15) of bonding material applied between the leading and trailing edges (16, 17) of the label (L) comprises a hot melt adhesive. The method set forth in any of claims 1 to 4 wherein a further strip of bonding material is applied to the trailing edge (16) (only) of said label (L). The method set forth in claim 5 wherein the bonding material applied to the trailing edge (16) of the label comprises a hot melt adhesive and/or solvent. The method set forth in any of claims 1 to 6 wherein said step of bonding the overlapped leading and trailing edges (16, 17) of the label (L) comprises heat sealing the overlapped edges (16, 17). The method set forth in any of claims 1 to 7 wherein said container (10) is a glass container. The method set forth in any of claims 1 to 7 wherein said container (10) comprises a plastic container. A package comprising a container (10) which includes a side wall (14) with an intermediate portion (P) which has a height which is a part of the entire height of the container (10) and a curvature so as to form a place (C) of greatest diameter on the curved portion (P), a rectangular label (L) of shrinkable material having a leading edge (17), a trailing edge (16) and longitudinal edges, said label (L) having a strip (15) of bonding material along a longitudinally extending intermediate line corresponding to the place (C) of greatest diameter on the curved portion (P), said strip (15) of bonding material being spaced from the leading and trailing edges (16, 17) of the label (L), said label (L) being wrapped about said curved portion (P) with the bonding material (15) engaging the container (10) at the place of greatest diameter (C), said leading and trailing edges (16, 17) of said label (L) being overlapped and bonded to one another, and said overlapped label (L) being shrunk about said curved portion (P). The packages set forth in claim 10 wherein said curved portion (P) of said container has a compound curvature (R₁, R₂) such that the crest line (C) of the curved portion (P) divides the curved portion (P) into portions of different size. The package set forth in claim 10 or 11 wherein strip (15) of bonding material is interrupted. The package set forth in any of claims 10 to 12 wherein the strip (15) of bonding material applied between the leading and trailing edges (16, 17) of the label (L) comprises a hot melt adhesive. The package set forth in claim 11 wherein the leading and trailing edges (17, 16) are bonded by hot melt adhesive, solvent or heat sealing. The package set forth in any of claims 10 to 14 wherein said container (10) is a glass container. The package set forth in any of claims 10 to 14 wherein said container (10) comprises a plastic container. The package set forth in any of claims 10 to 14 wherein said curved portion (P) of said container (10) is a recessed portion. The package set forth in any one of claims 10 to 17 wherein the vertical height of said curved portion (P) is a minor portion of the vertical height of the side wall (14) of the container (10) and the width of the label (L) is substantially equal to the vertical height of the curved portion (P).

Inventors: HECKMANN RUSSELL W, HERMAN JAMES A, SHIPLE LARRY P, TRAXLER WALTER E, HECKMANN, RUSSELL W., HERMAN, JAMES A., SHIPLE, LARRY P., TRAXLER, WALTER E.
Applicants: OWENS BROCKWAY GLASS CONTAINER, OWENS-BROCKWAY GLASS CONTAINER INC.
Application year: 1994
Main classification: B65C3
IPC codes: B65B53, B65D23, B65C9, B65C3